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Re: There's only one RIAA equalization for phono

Posted by J Epstein on October 29, 2001 at 07:41:16:
When the LP was developed, there were still multiple standards but they were soon consolidated into RIAA and a European standard which was the same as RIAA but with a subsonic filter. Short-lived LP EQ curves included the Decca standard, RIAA, and I think maybe two or three more. There were different, non-standard playback EQ settings in the 78 era. More info can be found in one of the reprints from Wireless World published by Old Colony Sound Lab, which contains a full-function preamp designed during the transition era with built-in switchable EQ settings. The reprint is:
ITEM #BKAA27 $16.95 Mullard Tube Circuits For Audio Amplifiers
There is also more info in Morgan Jones, Valve Amplifiers.
I have a friend who transfers 78s for reissue projects and he has several variables to consider: playback speed (78s were not all cut at the nominal 78 RPM); stylus shape; stylus material; playback EQ. He has a table of EQ settings and speeds that MOSTLY work for each label but there are always exceptions.
In contrast, us LP-heads have it easy!
-j